JP2001042553A - Electrophotographic photoreceptor, process cartridge and electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electrophotographic photoreceptor having high sensitivity, ensuring good electrification characteristics and small dark decay and ensuring stable potential characteristics and a good image in any environment from low temperature and low humidity to high temperature and high humidity and to obtain a process cartridge and an electrophotographic device each using the electrophotographic photoreceptor. SOLUTION: The electrophotographic photoreceptor has a photosensitive layer on the electrically conductive substrate by way of an intermediate layer comprising a metal oxide having a crystallinity of 0.7-1.0 formed by a sol-gel process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor, a process cartridge having the electrophotographic photoreceptor, and an electrophotographic apparatus. More specifically, the present invention relates to a method for forming an intermediate layer containing a specific material between a support and a photosensitive layer. The present invention relates to an electrophotographic photosensitive member having the same, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus.

[0002]

2. Description of the Related Art In general, in a Carlson type electrophotographic photoreceptor, when charging and exposure are repeated, a stable image density and a stable image with no background stain are formed. It has become important. For this reason, it has been proposed to provide a layer having a function as a barrier layer between the photosensitive layer and the support.

Further, there has been proposed a layer having a laminated structure in which a photosensitive layer is functionally separated into a charge generation layer and a charge transport layer. Generally, the charge generation layer is provided as an extremely thin layer having a thickness of about 0.5 μm, for example. Therefore, defects, dirt, deposits, scratches, and the like on the support surface cause the charge generation layer to have a non-uniform film thickness. Furthermore, recent efforts to improve image quality have revealed that it is effective to reduce the thickness of the charge transport layer. Therefore, if the thickness of the charge generation layer is non-uniform, it becomes more difficult to control the thickness of the charge transport layer, and the sensitivity of the photoreceptor becomes uneven, so that the charge generation layer should be as uniform as possible. Has been requested.

[0004] For this reason, it has been proposed to provide an intermediate layer having a function as a barrier layer and a function as an adhesive layer between the charge generation layer and the support.

[0005] Conventional layers provided between the photosensitive layer and the support include polyamides (JP-A-46-47344 and JP-A-52-25638) and polyesters (JP-A-52-20836). JP-A-54-267
No. 38), polyurethane (JP-A-49-10044).
JP, JP-A-53-89435), casein (JP-A-55-103556), polypeptide (JP-A-53-48523), polyvinyl alcohol (JP-A-52-100240) , Polyvinyl pyrrolidone (JP-A-48-30936), vinyl acetate-ethylene copolymer (JP-A-48-26141), and maleic anhydride ester polymer (JP-A-52-1).
0138), polyvinyl butyral (Japanese Unexamined Patent Publication No.
-90639, JP-A-58-106549), and a quaternary ammonium salt-containing polymer (JP-A-51-106549).
126149, JP-A-56-60448), ethyl cellulose (JP-A-55-143564) and the like are known.

In an electrophotographic photoreceptor using the above-described material as an intermediate layer, the resistance of the intermediate layer changes due to a change in temperature and humidity. It was difficult to obtain stable potential characteristics and image quality.

In addition, when the charge transport layer is thinned for the purpose of increasing the resolution, the chargeability is reduced by repeated use, and black spot-like defects (black spots) and fog are more likely to occur on the image. When the resistance of the intermediate layer fluctuates due to a change in humidity, the influence on the image tends to be more remarkable. Therefore, as the photoconductor becomes thinner, it is necessary to improve the intermediate layer at a higher level.

Japanese Patent Application Laid-Open No. 61-94057 discloses an intermediate layer containing an organometallic compound as a main component.
JP-287275 discloses an intermediate layer formed of a metal oxide formed by a vacuum thin film manufacturing method. Since the conductivity of the organic intermediate layer is caused by the presence of ions, the organic intermediate layer is easily affected by moisture, and the resistance from high temperature and high humidity to low temperature and low humidity cannot be controlled with a small fluctuation width. On the other hand, the inorganic intermediate layer has less environmental fluctuation than the organic material, the resistance value can be controlled by doping, and the electric (electronic) matching with the photosensitive layer is performed by controlling the ionization potential. There are advantages such as being able to.

However, the intermediate layer containing the above-mentioned organometallic compound as a main component has a large amount of organic substances remaining, and has a large amount of impurities and defects due to a small amount of bonding between metal atoms and oxygen atoms. Was still inadequate.
Therefore, the film has a large environmental change in film resistance and a low ionization potential, and has problems such as a large dark decay in electrophotographic characteristics.

The intermediate layer made of a metal oxide formed by the vacuum thin film manufacturing method has no problem in the tightness of the film, but has a composition for obtaining a sufficient ionization potential.
Defect control was difficult.

Further, if there are many lattice defects as in the intermediate layer formed by the above-described method, the metal element in the support is doped into the intermediate layer, or the metal element of the support is removed during the firing process. There is a problem that the resistance of the intermediate layer fluctuates and the effect as a barrier layer is reduced, and the environmental characteristics and electrophotographic characteristics of the photoreceptor are easily deteriorated.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic photosensitive member having high sensitivity, good charging characteristics and low dark decay, a process cartridge using the electrophotographic photosensitive member, and an electrophotographic apparatus. It is to be.

Another object of the present invention is to provide an electrophotographic photosensitive member capable of obtaining images with stable potential characteristics and images in all environments from low temperature and low humidity to high temperature and high humidity, and a process using the electrophotographic photosensitive member. An object of the present invention is to provide a cartridge and an electrophotographic apparatus.

[0014]

According to the present invention, in an electrophotographic photosensitive member having a photosensitive layer on a conductive support via an intermediate layer, the intermediate layer is formed by a sol-gel method with a crystallinity of 0.7 to 0.7. An electrophotographic photosensitive member comprising a metal oxide of 1.0, a process cartridge using the electrophotographic photosensitive member, and an electrophotographic apparatus are provided.

[0015]

Embodiments of the present invention will be described below in detail.

The intermediate layer is formed by applying a sol-gel hydrolyzate on a conductive support and baking it. The hydrolyzate of the sol-gel is prepared by adding a starting material to a solvent, adding an acid or a base, and hydrolyzing at an appropriate pH, temperature and time.

As starting materials, metal alkoxides,
Use is made of halides, oxides, hydroxides, dialkylamides, esters with organic acids or acid anhydrides, chelates with β-diketone or β-ketoamine or β-ketoester, and reaction products with alkanolamines. The starting materials can be used in combination of two or more. When zinc as an example, _{preferably, Zn (OAc) 2 · 2H} 2
Carboxylic acid esters such as O, Zn (AcAc) ₂ .H ₂
Chelates such as O, and alkyl zincs, particularly preferably alkyl zincs, are mentioned in terms of the tightness of the membrane.

As the solvent, those that dissolve the starting materials can be used. Typical solvents include alcohols, β
-Ketones such as diketone, and toluene and xylene can also be used. Particularly which was satisfactory in the present invention, when the zinc _{example, Zn (OAc) 2 · 2H} 2 O in ethanol, 1-butanol, 2-ethoxyethanol, diethylene glycol, Zn (AcAc) in ₂ · H ₂ O Ethanol, 2-ethoxyethanol, ethyl acetate, and zinc octylate are ethyl acetate and ethanol, zinc naphthenate is n-butanol, and alkyl zinc is sec-butanol, methyl acetoacetate, and ethylene glycol monophenyl ether. Among these solvents, besides those used merely for dissolving the starting materials, those used for the purpose of causing alcohol exchange reaction with the starting materials, and those used for controlling the rate of hydrolysis reaction .

The catalyst used for the hydrolysis may be an acid, a base, or the like, but it is preferable in the present invention that zinc is acetic acid and Zn (Ac) in Zn (OAc) ₂ .2H ₂ O.
Ac) ₂ · H ₂ O and alkyl zinc were hydrochloric acid.

As a coating method, a method such as a spray coating, a dip coating, a knife coating, and a roll coating is appropriately used.
The baking is performed at normal temperature or by heating. The atmosphere can be an air atmosphere, a nitrogen atmosphere, an oxygen atmosphere, an argon atmosphere, or the like.

Taking zinc oxide as an example, zinc oxide is generally represented by ZnO, but a composition deviating from the stoichiometric composition can be produced depending on the conditions of formation.

The thickness of the intermediate layer used in the present invention is preferably from 100 to 10 μm, more preferably from 500 to 10 μm.
5 μm.

The electrophotographic photoreceptor of the present invention uses a metal oxide film having a crystallinity of 0.7 to 1.0 as the intermediate layer to increase the residual potential under low temperature and low humidity and to increase the temperature under high temperature and high humidity. In this case, it is possible to prevent environmental fluctuations such as a decrease in dark area potential due to a decrease in barrier function.

Since the metal oxide film of the present invention hardly changes in volume resistance under each environment, an electrophotographic photoreceptor with little environmental change can be obtained when the metal oxide film is used as an intermediate layer. The resistance of a normal organic resin is reduced by about three digits from normal temperature and normal humidity to high temperature and high humidity, but the metal oxide as an inorganic material hardly changes. Furthermore, since the metal oxide film formed by using the sol-gel method is a uniform and dense film without pinholes, it is considered that the metal oxide film is not affected by environmental changes, particularly, humidity.

The dark decay of the metal oxide film became smaller as the metal oxide film became more likely to become an n-type semiconductor and the ionization potential became larger. Although the cause is not clear, the metal oxide that easily becomes an n-type semiconductor has a high performance of preventing injection of holes from the conductive support into the photosensitive layer, and the metal oxide having a higher ionization potential has a higher conductivity. It is considered that dark decay was reduced because the energy gap with the support became large and injection of holes from the conductive support into the photosensitive layer was unlikely to occur.

The metal oxide used in the present invention includes titanium oxide, aluminum oxide, indium oxide, tantalum oxide, zinc oxide, cerium oxide, magnesium oxide, tin oxide, iron oxide, zirconium oxide, etc., and is particularly preferable. Were zinc oxide, zirconium oxide, tin oxide and titanium oxide. It is preferable that the ionization potential of the intermediate layer is appropriately adjusted in accordance with the ionization potential of the conductive support and the charge generation layer.

It has also been found that the crystallinity of the intermediate layer affects the dark decay. The metal oxide film produced by the conventional method could obtain only a completely amorphous or polycrystalline oriented in a predetermined direction. Further, crystallization requires firing at a very high temperature or maintaining the substrate at a high temperature during film formation. However, by using the sol-gel method, a film crystallized by firing at a relatively low temperature could be produced. Further, it was found that the degree of crystallization can be freely changed as needed. The higher the crystallinity of the intermediate layer, the better, but the higher the crystallinity, the smaller the resistance of the film. Therefore, it is preferable to adjust the crystallinity. The crystallinity was good when it was 0.5 or more.

The support used in the present invention may be any one having conductivity, for example, aluminum,
Metals such as copper, chromium, nickel, zinc, and stainless steel molded on drums or sheets; metal foils such as aluminum and copper laminated on plastic films; aluminum, indium oxide, tin oxide, etc. deposited on plastic films Or a metal, a plastic film, paper, etc. provided with a conductive layer by applying a conductive material alone or with an appropriate binder resin.

The conductive material used for the conductive layer includes metal powders such as aluminum, copper, nickel and silver; metal foils and short metal fibers; conductive metal oxides such as antimony oxide, indium oxide and tin oxide. , Polypyrrole, polyaniline, polymer conductive materials such as polymer electrolytes, carbon fiber, carbon black, graphite powder,
Examples thereof include organic and inorganic electrolytes, and conductive powders whose surfaces are coated with these conductive materials.

Further, as the binder resin used for the conductive layer, polyamide, polyester, acrylic resin,
Polyamino acid ester, polyvinyl lactate, polycarbonate, polyvinyl formal, polyvinyl butyral,
Examples thereof include thermoplastic resins such as polyvinyl alkyl ether, polyalkylene ether, and polyurethane elastomer, and thermosetting resins such as thermosetting polyurethane, phenol resin, and epoxy resin.

The mixing ratio between the conductive material and the binder resin is about 5: 1 to 1: 5. This mixing ratio is determined in consideration of the resistance value, surface properties, coating suitability, and the like of the conductive layer.
When the conductive material is a powder, a mixture with a binder resin is prepared and used using a ball mill, a roll mill, a sand mill, or the like.

As other additives, a surfactant, a silane coupling agent, a titanate coupling agent, a silicone oil, a silicone leveling agent and the like may be added.

In the present invention, the photosensitive layer may be of a single layer type or of a laminated structure in which the function is separated into a charge generation layer and a charge transport layer.

The charge generation layer of the photoreceptor having a laminated structure is made of an azo pigment such as Sudan Red or Diane Blue, a quinone pigment such as pyrenequinone or anthantrone, a quinolinine pigment, a perylene pigment, an indigo pigment such as indigo or thioindigo, or an azulhenium salt pigment. A copper phthalocyanine, a charge generating material such as a phthalocyanine pigment such as oxytitanium phthalocyanine, is dispersed in a binder resin such as polyvinyl butyral, polystyrene, polyvinyl acetate, an acrylic resin, polyvinyl pyrrolidone, ethyl cellulose, and acetic acid-butyrate, and this dispersion is obtained. Is applied on the above-mentioned intermediate layer. like this,
The thickness of the charge generation layer is preferably 5 μm or less, more preferably 0.05 to 2 μm.

The charge transport layer provided on the charge generation layer is formed of a polycyclic aromatic compound having a structure such as biphenylene, anthracene, pyrene, or phenanthrene in a main chain or a side chain; It is formed using a coating solution in which a charge transporting material such as a nitrogen-containing cyclic compound, a hydrazone compound, a styryl compound or the like is dissolved in a resin having a film-forming property. The reason for forming the film in this manner is that the charge transporting material generally has a low molecular weight and is poor in film forming property by itself.

As the resin having such a film forming property,
Examples include polyester, polycarbonate, polymethacrylate, and polystyrene. The thickness of the charge transport layer is preferably 5 to 40 µm, more preferably 10 to 40 µm.
30 μm.

In the present invention, an organic photoconductive polymer layer such as polyvinyl carbazole and polyvinyl anthracene, a selenium vapor deposition layer, a selenium-tellurium vapor deposition layer, an amorphous silicon layer and the like can also be used for the photosensitive layer.

In the present invention, a layer structure in which a charge generation layer is provided on a charge transport layer is also possible in addition to the above-described layer structure as a structure of the photosensitive layer. In the present invention, a protective layer can be further provided on the photosensitive layer.

The protective layer is provided for the purpose of protecting the surface of the photoreceptor. Materials used for the protective layer include ABS resin, olefin-vinyl monomer copolymer, chlorinated polyether, allyl resin, phenol resin, polyacetal. , Polyamide, polyamideimide, polyacrylate, polyallyl sulfone, polybutylene, polybutylene terephthalate, polycarbonate, polyether sulfone, polyethylene, polyethylene terephthalate, polyimide, acrylic resin, polymethylpentene, polypropylene, polyphenylene oxide, polysulfone, polystyrene, AS resin , Butadiene-styrene copolymer, polyurethane, polyvinyl chloride, polyvinylidene chloride, epoxy resin and the like.

In the protective layer, a fluororesin such as polytetrafluoroethylene, a silicone resin, and an inorganic material such as titanium oxide, tin oxide and potassium titanate are dispersed in these resins for the purpose of improving abrasion resistance. Can be added. As a method of forming the protective layer,
Normal coating methods are used. In addition, the thickness of the protective layer is 0.1.
About 6 to 10 μm is appropriate.

FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention.

In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is driven to rotate around a shaft 2 in a direction of an arrow at a predetermined peripheral speed. The photoreceptor 1 rotates during the rotation process.
The peripheral surface is uniformly charged at a predetermined positive or negative potential by the primary charging means 3, and then, the time-series electricity of the target image information output from exposure means (not shown) such as slit exposure or laser beam scanning exposure. The exposure light 4 which has been enhanced and modulated according to the digital image signal is received. In this way, an electrostatic latent image corresponding to the target image information is sequentially formed on the peripheral surface of the photoconductor 1.

The formed electrostatic latent image is then transferred to developing means 5
The toner image thus developed is transferred from a paper supply unit (not shown) between the photoconductor 1 and the transfer unit 6 in synchronization with the rotation of the photoconductor 1 to a transfer material 7 fed and fed. Then, the toner image formed and carried on the surface of the photoconductor 1 is sequentially transferred by the transfer unit 6.

The transfer material 7 to which the toner image has been transferred is separated from the surface of the photoreceptor, introduced into the image fixing means 8 and subjected to image fixing, and is discharged out of the apparatus as an image formed product (print, copy). .

The surface of the photoreceptor 1 after the image transfer is cleaned and cleaned by removing the untransferred toner by the cleaning means 9, and is further subjected to a pre-exposure light 10 from a pre-exposure means (not shown).
Is used for image formation repeatedly after the charge removal processing. When the primary charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure is not necessarily required.

In the present invention, a plurality of components such as the above-described electrophotographic photosensitive member 1, primary charging means 3, developing means 5, and cleaning means 9 are integrally connected as a process cartridge. The process cartridge may be configured to be detachable from a main body of an electrophotographic apparatus such as a copying machine or a laser beam printer. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photoreceptor 1 to form a cartridge, and is detachably attached to the apparatus main body using a guide unit such as a rail 12 of the apparatus main body. Process cartridge 1
It can be 1.

When the electrophotographic apparatus is a copying machine or a printer, the exposure light 4 is reflected light or transmitted light from the original, or the original is read by a sensor, converted into a signal, and a laser beam is emitted in accordance with the signal. Beam scanning, LED
Light emitted by driving the array, driving the liquid crystal shutter array, and the like.

The electrophotographic photosensitive member of the present invention can be used not only for an electrophotographic copying machine but also for a laser beam printer,
It can be widely used in electrophotographic applications such as CRT printers, LED printers, faxes, liquid crystal printers, and laser plate making.

FIG. 2 briefly describes the electrophotographic apparatus of the present invention.

First, the document G is set on the document table 20 with the surface to be copied facing downward. Next, copying is started by pressing the copy button. Document illumination lamp, short focus lens array, CCD sensor unit 29
Scans while irradiating the original, the irradiating scanning light is imaged by the short focus lens array and
It is incident on the D sensor.

The CCD sensor includes a light receiving section, a transfer section, and an output section. The optical signal is converted into an electric signal in the CCD light receiving unit, and is sequentially transferred to the output unit in synchronization with the clock pulse in the transfer unit. The output unit converts the charge signal into a voltage signal, amplifies the voltage signal, reduces the impedance, and outputs the signal. The analog signal obtained in this way is converted to a digital signal, and further converted to a digital signal for performing image processing for optimizing resolution and gradation according to the characteristics of the image and outputting the digital signal. Sent to the department.

When outputting from a computer or the like, resolution, gradation reproduction method and the like are selected, processed so as to obtain a desired image, converted, and sent to a printer unit. The printer unit receives the image signal and forms an electrostatic latent image as follows. The photosensitive drum 1 of the present invention
It is driven to rotate at a predetermined peripheral speed around the center support shaft, and receives a positive or negative uniform charging process of a predetermined voltage by the charging means 3 during the rotation process, and the uniform charging surface converts the image signal into an image signal. Corresponding ON / OFF light emitted from the solid-state laser element is scanned by a rotating polygon mirror rotating at high speed, so that an electrostatic latent image corresponding to the original image is sequentially formed on the surface of the photosensitive drum 1. .

Normally, an image that can be identified with the naked eye is 40
Although the resolution is about 0 dpi and about 256 gradations, the minimum resolution area in this case is about 16 μm ² , which corresponds to a resolution of 5000 dpi or more.

In order to realize such a high resolution, it is necessary to reduce the spot area of the light beam. However, simply reducing the spot area cannot provide high resolution. The product of layer thickness is 2000
The thickness is preferably 0 μm ³ or less.

[0055]

The present invention will be described in more detail with reference to the following examples. In addition. “Parts” indicates parts by weight.

First, a specific example of the preparation of the coating liquid used for forming the intermediate layer of the present invention will be described.

[0057] "Formulation Example 1" _{Zn (OAc) 2 · 2H 2} O
After dissolving 13.5 g in a mixed solution of 62 g of water / 75 g of ethanol, 2 g of 6N hydrochloric acid was added and reflux was performed for 30 minutes. Then, 5 g of acetic acid, 1-butanol 10
g, 2-ethoxyethanol (20 g) and diethylene glycol (5 g) to prepare a 2.5 wt% ZnO solution.

"Formulation Example 2" Zn (AcAc) ₂ .H ₂ O
8.45 g was dissolved in 26.15 g of ethanol, 5.4 g of 6N hydrochloric acid was added dropwise, and the mixture was refluxed. After cooling,
It was prepared by adding 10 g of 2-ethoxyethanol, 5 g of ethyl acetate and 5 g of water.

"Formulation Example 3" Zinc octylate (Nikka Octex Zn / mineral spirit solution) 26.7 g was prepared by diluting with 73.3 g of an equal mixture of ethyl acetate / ethanol.

"Formulation Example 4" Zinc naphthenate (Nikka Naphtex Zn / mineral spirit solution) was used as it was.

"Formulation Example 5" 75 g of zinc naphthenate (Nikkanaphtex Zn / mineral spirit solution) was added to n-
It was diluted and prepared with 25 g of butanol.

"Formulation Example 6" diethyl zinc (0.99 mol
1 / l hexane solution) 33 g of methyl acetoacetate 1
The mixture was added dropwise to a mixture of 1.61 g / sec-butanol (40.57 g). After the heat generation was stopped, 34.54 g of ethylene glycol monophenyl ether was added dropwise under a nitrogen flow, and the mixture was allowed to stand overnight. Add 0.001N hydrochloric acid 0.2
A mixed solution of 3 g / sec-butanol (59.77 g) was added dropwise to prepare.

"Formulation Example 7" Titanium isopropoxide was added to 1,3 butadiol, and nitric acid was added dropwise with stirring, followed by stirring overnight to prepare.

Formulation Example 8 Aluminum isopropoxide was added to isopropanol, water and acetic acid were added dropwise with stirring, and the mixture was stirred overnight to prepare.

Example 1 An aluminum plate (5 cm × 5
cm), the mixture was immersed and applied at 500 ° C. for 30 minutes in an air atmosphere to form a 0.5 μm-thick zinc oxide film. Table 1 shows the crystallinity of the zinc oxide film.

The degree of crystallinity Xc is determined from the intensity of the diffraction peak measured by the X-ray diffraction method using the powder once prepared.
Determined by the following equation: Crystallinity Xc = peak intensity of sample / peak intensity of single crystal

Next, on the intermediate layer, oxytitanium phthalocyanine (TiOPc) having strong peaks at 23.9 ° and 27.1 ° of Bragg angles (2θ ± 0.2 °) in characteristic X-ray diffraction of CuKα. After 4 parts of 2 parts of polyvinyl butyral (trade name: Esrec BM-2 manufactured by Sekisui Chemical) and 80 parts of cyclohexanone were dispersed for 4 hours by a sand mill using 1 mmφ glass beads, 115 parts of methyl ethyl ketone was added, and dispersion for the charge generating layer was added. A liquid was prepared. This is applied on the intermediate layer by a dipping method, and the film thickness is set to 0.
A 3 μm charge generation layer was formed.

Next, 10 parts of an amine compound having the following structural formula:

[0069]

Embedded image And polycarbonate (weight average molecular weight 46,000) 1
0 parts: 20 parts of dichloromethane / 40 parts of monochlorobenzene
Of the mixed solvent. This paint is applied on the charge generation layer by the dipping method, and dried at 120 ° C. for 1 hour.
A charge transport layer having a thickness of 25 μm was formed.

The electrophotographic photoreceptor piece thus manufactured was subjected to a temperature of 20 ° C./humidity of 50% RH (relative humidity) (N /
N), temperature 15 ° C / humidity 10% RH (L / L), temperature 3
After humidity control in each environment of 0 ° C./85% RH (H / H) overnight, an electrostatic copying paper test apparatus Mode manufactured by Kawaguchi Electric Co., Ltd.
Using EP-8200, evaluation was made as follows.

First, after exposure at an illuminance of 10 lux and charge elimination, corona charging was performed at a discharge voltage of -4.5 kV, and the potential before and after holding for 3 seconds in a dark place was examined. Table 1 shows the results of the initial potential V0 (V) and the dark decay Vdd (V) for 3 seconds in each environment.

(Examples 2 to 4) Aluminum plate (5 cm)
× 5 cm) after dip coating the formulation liquid of Formulation Examples 6 to 8,
Baking at 500 ° C. for 30 minutes in an air atmosphere to obtain a film thickness of 0.
A 5 μm metal oxide film was formed. Table 1 shows the crystallinity Xc of these intermediate layers. The electrophotographic photosensitive member thus produced was evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 5 An intermediate layer was prepared in the same manner as in Example 2, and 3 parts of a disazo pigment having the following structural formula was prepared.

[0074]

Embedded image After dispersing 2 parts of polyvinyl benzal (75% of benzal conversion, weight average molecular weight of 13000) and 35 parts of cyclohexanone for 8 hours by a sand mill using 1 mmφ glass beads, 60 parts of methyl ethyl ketone (MEK) is added to form a charge generating layer. A dispersion was prepared. This dispersion was applied onto the above-mentioned intermediate layer by dip coating and dried at 80 ° C. for 20 minutes to form a charge generation layer having a thickness of 0.2 μm.

Next, a styryl compound 10 of the following structural formula
Department,

[0076]

Embedded image And polycarbonate (weight average molecular weight 46,000) 1
0 parts: 20 parts of dichloromethane / 40 parts of monochlorobenzene
Of the mixed solvent, and the resulting solution was applied onto the above-mentioned charge generating layer by dip coating and dried at 120 ° C. for 60 minutes to form a charge transporting layer having a thickness of 13 μm. The electrophotographic photoreceptor thus produced was evaluated in the same manner as in Example 1.
Table 1 shows the results.

(Comparative Example 1 and Comparative Example 2) Instead of the zinc oxide film, the intermediate layer in Examples 1 and 5 was replaced with N-methoxydimethylated 6 nylon (weight average molecular weight: 120,000, methoxydimethyl group substitution rate: 33%). ), Except that the electrophotographic photoreceptor was manufactured in the same manner as in Examples 1 and 5.
Comparative Examples 1 and 2 were used. The electrophotographic photosensitive member was evaluated in the same manner as in Example 1. Table 1 shows the results.

(Comparative Example 3) An electrophotographic photosensitive member was manufactured in the same manner as in Example 1 except that a zinc oxide film (0.5 μm in thickness) formed by a vacuum deposition method was used for the intermediate layer in Example 1. Comparative Example 3 was used. The crystallinity of this intermediate layer was measured to be 0.65. The electrophotographic photosensitive member was evaluated in the same manner as in Example 1. Table 1 shows the results.

[0079]

[Table 1]

Example 6 An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that the aluminum plate of Example 2 was replaced with an aluminum cylinder (φ30 mm × 260 mm). The electrophotographic photoreceptor thus produced is
Attach it to a laser printer of a reversal development system in which the process of charging-exposure-development-transfer-cleaning is repeated at a cycle of 2.0 seconds.
The electrophotographic characteristics were evaluated in an environment of 0% RH: N / N and high temperature and high humidity (temperature 30 ° C./humidity 85% RH: H / H).

As a result, as shown in Table 2, in the electrophotographic photosensitive member of Example 6, the dark portion potential (Vd1) and the bright portion potential (V
111), a sufficient potential contrast was obtained, and the dark area potential (Vd2) was stable even under high temperature and high humidity, and a good image without black spot-like defects (black spots) and fog was obtained. . Further, the electrophotographic photoreceptor is continuously heated at a high temperature and high humidity (temperature: 30 ° C., humidity: 85% RH: H / H).
When zero images were output, a stable image was obtained with little increase in the light-part potential (Vl).

Comparative Example 4 An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that the aluminum plate of Comparative Example 1 was replaced with an aluminum cylinder (30 mmφ × 260 mm). This electrophotographic photosensitive member was evaluated in the same manner as in Example 6. As a result, as shown in Table 2, black spots occurred under high temperature and high humidity, and fog occurred after an endurance test.

Comparative Example 5 Electrophotography was performed in the same manner as in Comparative Example 3 except that the aluminum plate of the intermediate layer of the zinc oxide film produced by the vacuum evaporation method of Comparative Example 3 was replaced with an aluminum cylinder (30 mmφ × 260 mm). A photoreceptor was produced.
This electrophotographic photosensitive member was evaluated in the same manner as in Comparative Example 3. As a result, as shown in Table 2, black spots occurred under high temperature and high humidity, and fog occurred after an endurance test.

[0084]

[Table 2]

Example 7 An electrophotographic photosensitive member was prepared in the same manner as in Example 2 except that the aluminum cylinder in Example 2 was replaced with a cylinder having an outer diameter of 30 mm and the charge transport layer was 10 μm. Using the same apparatus as in Example 6, under high temperature and high humidity (temperature 30 ° C., humidity 85% RH:
(H / H), 1000 images were output continuously. As a result, a stable image was obtained with little increase in the light-part potential (V1).

Comparative Example 6 An electrophotographic photoreceptor was produced in the same manner as in Comparative Example 4, except that the aluminum cylinder of Comparative Example 4 was changed to a cylinder having an outer diameter of 30 mm, and the thickness of the charge transport layer was changed to 10 μm. Was prepared. This electrophotographic photosensitive member was evaluated in the same manner as in Example 7. Table 3 shows the results.
As shown in Table 2, black spots occurred under high temperature and high humidity, and fog occurred after the durability test.

Comparative Example 7 The same procedure as in Comparative Example 5 was carried out except that the aluminum cylinder of the electrophotographic photosensitive member of Comparative Example 5 was changed to a cylinder having an outer diameter of 30 mm, and the thickness of the charge transport layer was changed to 10 μm. Thus, an electrophotographic photosensitive member was manufactured.
This electrophotographic photosensitive member was evaluated in the same manner as in Example 7. As a result, as shown in Table 3, black spots occurred under high temperature and high humidity, and fog occurred after the durability test.

[0088]

[Table 3]

[0089]

According to the present invention, an electrophotographic photoreceptor having a small dark decay and capable of obtaining stable potential characteristics and a good image in all environments from low temperature and low humidity to high temperature and high humidity, and the electrophotographic photoreceptor It has become possible to provide a process cartridge and an electrophotographic apparatus using the same.

[Brief description of the drawings]

FIG. 1 shows a schematic configuration of an electrophotographic apparatus having a process cartridge having an electrophotographic photosensitive member of the present invention.

FIG. 2 is a schematic view of the electrophotographic apparatus of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor 2 shaft 3 charging means 4 exposure light 5 developing means 6 transfer means 7 transfer material 8 fixing means 9 cleaning means 10 pre-exposure light 11 process cartridge 12 guide means 20 platen 29 unit G original

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masataka Kawahara 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Keiko Hiraoka 3- 30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the Company (72) Inventor ▲ Yoshi ▼ Kazuo Naga 3-2-3 Shimomaruko, Ota-ku, Tokyo F-term (reference) 2H068 AA35 AA44 CA22 CA33 CA60 FA07 FA12 FA27 2H071 BA04 BA13 DA06 DA08 DA09 DA15

Claims (5)

[Claims] 1. An electrophotographic photosensitive member having a photosensitive layer on a conductive support via an intermediate layer, wherein the intermediate layer is formed by a sol-gel method and has a crystallinity of 0.7 to 1.0. An electrophotographic photosensitive member comprising a film. 2. The electrophotographic photosensitive member according to claim 1, wherein the metal oxide of the intermediate layer is at least one of zinc oxide, titanium oxide and aluminum oxide, which is an n-type semiconductor. 3. A charging unit for charging the electrophotographic photosensitive member according to claim 1 or 2, a developing unit for developing the electrophotographic photosensitive member on which an electrostatic latent image is formed with toner, and A process cartridge which is integrally supported together with at least one means selected from the group consisting of a cleaning means for recovering toner remaining on a photoreceptor after a transfer step, and is detachable from an electrophotographic apparatus main body. 4. An electrophotographic photosensitive member according to claim 1 or 2, a charging unit for charging the electrophotographic photosensitive member, an exposure unit for exposing the charged electrophotographic photosensitive member to form an electrostatic latent image, and An electrophotographic apparatus comprising: developing means for developing an electrophotographic photosensitive member on which an electrostatic latent image is formed with toner; and transfer means for transferring a toner image on a transfer material. 5. The electrophotographic apparatus according to claim 4, wherein the product of the spot area of the light beam and the thickness of the charge transport layer is 20,000 μm ³ or less.